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Merge tag 'powerpc-4.6-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc...
[deliverable/linux.git] / net / core / sock.c
1 /*
2 * INET An implementation of the TCP/IP protocol suite for the LINUX
3 * operating system. INET is implemented using the BSD Socket
4 * interface as the means of communication with the user level.
5 *
6 * Generic socket support routines. Memory allocators, socket lock/release
7 * handler for protocols to use and generic option handler.
8 *
9 *
10 * Authors: Ross Biro
11 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
12 * Florian La Roche, <flla@stud.uni-sb.de>
13 * Alan Cox, <A.Cox@swansea.ac.uk>
14 *
15 * Fixes:
16 * Alan Cox : Numerous verify_area() problems
17 * Alan Cox : Connecting on a connecting socket
18 * now returns an error for tcp.
19 * Alan Cox : sock->protocol is set correctly.
20 * and is not sometimes left as 0.
21 * Alan Cox : connect handles icmp errors on a
22 * connect properly. Unfortunately there
23 * is a restart syscall nasty there. I
24 * can't match BSD without hacking the C
25 * library. Ideas urgently sought!
26 * Alan Cox : Disallow bind() to addresses that are
27 * not ours - especially broadcast ones!!
28 * Alan Cox : Socket 1024 _IS_ ok for users. (fencepost)
29 * Alan Cox : sock_wfree/sock_rfree don't destroy sockets,
30 * instead they leave that for the DESTROY timer.
31 * Alan Cox : Clean up error flag in accept
32 * Alan Cox : TCP ack handling is buggy, the DESTROY timer
33 * was buggy. Put a remove_sock() in the handler
34 * for memory when we hit 0. Also altered the timer
35 * code. The ACK stuff can wait and needs major
36 * TCP layer surgery.
37 * Alan Cox : Fixed TCP ack bug, removed remove sock
38 * and fixed timer/inet_bh race.
39 * Alan Cox : Added zapped flag for TCP
40 * Alan Cox : Move kfree_skb into skbuff.c and tidied up surplus code
41 * Alan Cox : for new sk_buff allocations wmalloc/rmalloc now call alloc_skb
42 * Alan Cox : kfree_s calls now are kfree_skbmem so we can track skb resources
43 * Alan Cox : Supports socket option broadcast now as does udp. Packet and raw need fixing.
44 * Alan Cox : Added RCVBUF,SNDBUF size setting. It suddenly occurred to me how easy it was so...
45 * Rick Sladkey : Relaxed UDP rules for matching packets.
46 * C.E.Hawkins : IFF_PROMISC/SIOCGHWADDR support
47 * Pauline Middelink : identd support
48 * Alan Cox : Fixed connect() taking signals I think.
49 * Alan Cox : SO_LINGER supported
50 * Alan Cox : Error reporting fixes
51 * Anonymous : inet_create tidied up (sk->reuse setting)
52 * Alan Cox : inet sockets don't set sk->type!
53 * Alan Cox : Split socket option code
54 * Alan Cox : Callbacks
55 * Alan Cox : Nagle flag for Charles & Johannes stuff
56 * Alex : Removed restriction on inet fioctl
57 * Alan Cox : Splitting INET from NET core
58 * Alan Cox : Fixed bogus SO_TYPE handling in getsockopt()
59 * Adam Caldwell : Missing return in SO_DONTROUTE/SO_DEBUG code
60 * Alan Cox : Split IP from generic code
61 * Alan Cox : New kfree_skbmem()
62 * Alan Cox : Make SO_DEBUG superuser only.
63 * Alan Cox : Allow anyone to clear SO_DEBUG
64 * (compatibility fix)
65 * Alan Cox : Added optimistic memory grabbing for AF_UNIX throughput.
66 * Alan Cox : Allocator for a socket is settable.
67 * Alan Cox : SO_ERROR includes soft errors.
68 * Alan Cox : Allow NULL arguments on some SO_ opts
69 * Alan Cox : Generic socket allocation to make hooks
70 * easier (suggested by Craig Metz).
71 * Michael Pall : SO_ERROR returns positive errno again
72 * Steve Whitehouse: Added default destructor to free
73 * protocol private data.
74 * Steve Whitehouse: Added various other default routines
75 * common to several socket families.
76 * Chris Evans : Call suser() check last on F_SETOWN
77 * Jay Schulist : Added SO_ATTACH_FILTER and SO_DETACH_FILTER.
78 * Andi Kleen : Add sock_kmalloc()/sock_kfree_s()
79 * Andi Kleen : Fix write_space callback
80 * Chris Evans : Security fixes - signedness again
81 * Arnaldo C. Melo : cleanups, use skb_queue_purge
82 *
83 * To Fix:
84 *
85 *
86 * This program is free software; you can redistribute it and/or
87 * modify it under the terms of the GNU General Public License
88 * as published by the Free Software Foundation; either version
89 * 2 of the License, or (at your option) any later version.
90 */
91
92 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
93
94 #include <linux/capability.h>
95 #include <linux/errno.h>
96 #include <linux/errqueue.h>
97 #include <linux/types.h>
98 #include <linux/socket.h>
99 #include <linux/in.h>
100 #include <linux/kernel.h>
101 #include <linux/module.h>
102 #include <linux/proc_fs.h>
103 #include <linux/seq_file.h>
104 #include <linux/sched.h>
105 #include <linux/timer.h>
106 #include <linux/string.h>
107 #include <linux/sockios.h>
108 #include <linux/net.h>
109 #include <linux/mm.h>
110 #include <linux/slab.h>
111 #include <linux/interrupt.h>
112 #include <linux/poll.h>
113 #include <linux/tcp.h>
114 #include <linux/init.h>
115 #include <linux/highmem.h>
116 #include <linux/user_namespace.h>
117 #include <linux/static_key.h>
118 #include <linux/memcontrol.h>
119 #include <linux/prefetch.h>
120
121 #include <asm/uaccess.h>
122
123 #include <linux/netdevice.h>
124 #include <net/protocol.h>
125 #include <linux/skbuff.h>
126 #include <net/net_namespace.h>
127 #include <net/request_sock.h>
128 #include <net/sock.h>
129 #include <linux/net_tstamp.h>
130 #include <net/xfrm.h>
131 #include <linux/ipsec.h>
132 #include <net/cls_cgroup.h>
133 #include <net/netprio_cgroup.h>
134 #include <linux/sock_diag.h>
135
136 #include <linux/filter.h>
137 #include <net/sock_reuseport.h>
138
139 #include <trace/events/sock.h>
140
141 #ifdef CONFIG_INET
142 #include <net/tcp.h>
143 #endif
144
145 #include <net/busy_poll.h>
146
147 static DEFINE_MUTEX(proto_list_mutex);
148 static LIST_HEAD(proto_list);
149
150 /**
151 * sk_ns_capable - General socket capability test
152 * @sk: Socket to use a capability on or through
153 * @user_ns: The user namespace of the capability to use
154 * @cap: The capability to use
155 *
156 * Test to see if the opener of the socket had when the socket was
157 * created and the current process has the capability @cap in the user
158 * namespace @user_ns.
159 */
160 bool sk_ns_capable(const struct sock *sk,
161 struct user_namespace *user_ns, int cap)
162 {
163 return file_ns_capable(sk->sk_socket->file, user_ns, cap) &&
164 ns_capable(user_ns, cap);
165 }
166 EXPORT_SYMBOL(sk_ns_capable);
167
168 /**
169 * sk_capable - Socket global capability test
170 * @sk: Socket to use a capability on or through
171 * @cap: The global capability to use
172 *
173 * Test to see if the opener of the socket had when the socket was
174 * created and the current process has the capability @cap in all user
175 * namespaces.
176 */
177 bool sk_capable(const struct sock *sk, int cap)
178 {
179 return sk_ns_capable(sk, &init_user_ns, cap);
180 }
181 EXPORT_SYMBOL(sk_capable);
182
183 /**
184 * sk_net_capable - Network namespace socket capability test
185 * @sk: Socket to use a capability on or through
186 * @cap: The capability to use
187 *
188 * Test to see if the opener of the socket had when the socket was created
189 * and the current process has the capability @cap over the network namespace
190 * the socket is a member of.
191 */
192 bool sk_net_capable(const struct sock *sk, int cap)
193 {
194 return sk_ns_capable(sk, sock_net(sk)->user_ns, cap);
195 }
196 EXPORT_SYMBOL(sk_net_capable);
197
198 /*
199 * Each address family might have different locking rules, so we have
200 * one slock key per address family:
201 */
202 static struct lock_class_key af_family_keys[AF_MAX];
203 static struct lock_class_key af_family_slock_keys[AF_MAX];
204
205 /*
206 * Make lock validator output more readable. (we pre-construct these
207 * strings build-time, so that runtime initialization of socket
208 * locks is fast):
209 */
210 static const char *const af_family_key_strings[AF_MAX+1] = {
211 "sk_lock-AF_UNSPEC", "sk_lock-AF_UNIX" , "sk_lock-AF_INET" ,
212 "sk_lock-AF_AX25" , "sk_lock-AF_IPX" , "sk_lock-AF_APPLETALK",
213 "sk_lock-AF_NETROM", "sk_lock-AF_BRIDGE" , "sk_lock-AF_ATMPVC" ,
214 "sk_lock-AF_X25" , "sk_lock-AF_INET6" , "sk_lock-AF_ROSE" ,
215 "sk_lock-AF_DECnet", "sk_lock-AF_NETBEUI" , "sk_lock-AF_SECURITY" ,
216 "sk_lock-AF_KEY" , "sk_lock-AF_NETLINK" , "sk_lock-AF_PACKET" ,
217 "sk_lock-AF_ASH" , "sk_lock-AF_ECONET" , "sk_lock-AF_ATMSVC" ,
218 "sk_lock-AF_RDS" , "sk_lock-AF_SNA" , "sk_lock-AF_IRDA" ,
219 "sk_lock-AF_PPPOX" , "sk_lock-AF_WANPIPE" , "sk_lock-AF_LLC" ,
220 "sk_lock-27" , "sk_lock-28" , "sk_lock-AF_CAN" ,
221 "sk_lock-AF_TIPC" , "sk_lock-AF_BLUETOOTH", "sk_lock-IUCV" ,
222 "sk_lock-AF_RXRPC" , "sk_lock-AF_ISDN" , "sk_lock-AF_PHONET" ,
223 "sk_lock-AF_IEEE802154", "sk_lock-AF_CAIF" , "sk_lock-AF_ALG" ,
224 "sk_lock-AF_NFC" , "sk_lock-AF_VSOCK" , "sk_lock-AF_KCM" ,
225 "sk_lock-AF_MAX"
226 };
227 static const char *const af_family_slock_key_strings[AF_MAX+1] = {
228 "slock-AF_UNSPEC", "slock-AF_UNIX" , "slock-AF_INET" ,
229 "slock-AF_AX25" , "slock-AF_IPX" , "slock-AF_APPLETALK",
230 "slock-AF_NETROM", "slock-AF_BRIDGE" , "slock-AF_ATMPVC" ,
231 "slock-AF_X25" , "slock-AF_INET6" , "slock-AF_ROSE" ,
232 "slock-AF_DECnet", "slock-AF_NETBEUI" , "slock-AF_SECURITY" ,
233 "slock-AF_KEY" , "slock-AF_NETLINK" , "slock-AF_PACKET" ,
234 "slock-AF_ASH" , "slock-AF_ECONET" , "slock-AF_ATMSVC" ,
235 "slock-AF_RDS" , "slock-AF_SNA" , "slock-AF_IRDA" ,
236 "slock-AF_PPPOX" , "slock-AF_WANPIPE" , "slock-AF_LLC" ,
237 "slock-27" , "slock-28" , "slock-AF_CAN" ,
238 "slock-AF_TIPC" , "slock-AF_BLUETOOTH", "slock-AF_IUCV" ,
239 "slock-AF_RXRPC" , "slock-AF_ISDN" , "slock-AF_PHONET" ,
240 "slock-AF_IEEE802154", "slock-AF_CAIF" , "slock-AF_ALG" ,
241 "slock-AF_NFC" , "slock-AF_VSOCK" ,"slock-AF_KCM" ,
242 "slock-AF_MAX"
243 };
244 static const char *const af_family_clock_key_strings[AF_MAX+1] = {
245 "clock-AF_UNSPEC", "clock-AF_UNIX" , "clock-AF_INET" ,
246 "clock-AF_AX25" , "clock-AF_IPX" , "clock-AF_APPLETALK",
247 "clock-AF_NETROM", "clock-AF_BRIDGE" , "clock-AF_ATMPVC" ,
248 "clock-AF_X25" , "clock-AF_INET6" , "clock-AF_ROSE" ,
249 "clock-AF_DECnet", "clock-AF_NETBEUI" , "clock-AF_SECURITY" ,
250 "clock-AF_KEY" , "clock-AF_NETLINK" , "clock-AF_PACKET" ,
251 "clock-AF_ASH" , "clock-AF_ECONET" , "clock-AF_ATMSVC" ,
252 "clock-AF_RDS" , "clock-AF_SNA" , "clock-AF_IRDA" ,
253 "clock-AF_PPPOX" , "clock-AF_WANPIPE" , "clock-AF_LLC" ,
254 "clock-27" , "clock-28" , "clock-AF_CAN" ,
255 "clock-AF_TIPC" , "clock-AF_BLUETOOTH", "clock-AF_IUCV" ,
256 "clock-AF_RXRPC" , "clock-AF_ISDN" , "clock-AF_PHONET" ,
257 "clock-AF_IEEE802154", "clock-AF_CAIF" , "clock-AF_ALG" ,
258 "clock-AF_NFC" , "clock-AF_VSOCK" , "clock-AF_KCM" ,
259 "clock-AF_MAX"
260 };
261
262 /*
263 * sk_callback_lock locking rules are per-address-family,
264 * so split the lock classes by using a per-AF key:
265 */
266 static struct lock_class_key af_callback_keys[AF_MAX];
267
268 /* Take into consideration the size of the struct sk_buff overhead in the
269 * determination of these values, since that is non-constant across
270 * platforms. This makes socket queueing behavior and performance
271 * not depend upon such differences.
272 */
273 #define _SK_MEM_PACKETS 256
274 #define _SK_MEM_OVERHEAD SKB_TRUESIZE(256)
275 #define SK_WMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
276 #define SK_RMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
277
278 /* Run time adjustable parameters. */
279 __u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX;
280 EXPORT_SYMBOL(sysctl_wmem_max);
281 __u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX;
282 EXPORT_SYMBOL(sysctl_rmem_max);
283 __u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX;
284 __u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX;
285
286 /* Maximal space eaten by iovec or ancillary data plus some space */
287 int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512);
288 EXPORT_SYMBOL(sysctl_optmem_max);
289
290 int sysctl_tstamp_allow_data __read_mostly = 1;
291
292 struct static_key memalloc_socks = STATIC_KEY_INIT_FALSE;
293 EXPORT_SYMBOL_GPL(memalloc_socks);
294
295 /**
296 * sk_set_memalloc - sets %SOCK_MEMALLOC
297 * @sk: socket to set it on
298 *
299 * Set %SOCK_MEMALLOC on a socket for access to emergency reserves.
300 * It's the responsibility of the admin to adjust min_free_kbytes
301 * to meet the requirements
302 */
303 void sk_set_memalloc(struct sock *sk)
304 {
305 sock_set_flag(sk, SOCK_MEMALLOC);
306 sk->sk_allocation |= __GFP_MEMALLOC;
307 static_key_slow_inc(&memalloc_socks);
308 }
309 EXPORT_SYMBOL_GPL(sk_set_memalloc);
310
311 void sk_clear_memalloc(struct sock *sk)
312 {
313 sock_reset_flag(sk, SOCK_MEMALLOC);
314 sk->sk_allocation &= ~__GFP_MEMALLOC;
315 static_key_slow_dec(&memalloc_socks);
316
317 /*
318 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward
319 * progress of swapping. SOCK_MEMALLOC may be cleared while
320 * it has rmem allocations due to the last swapfile being deactivated
321 * but there is a risk that the socket is unusable due to exceeding
322 * the rmem limits. Reclaim the reserves and obey rmem limits again.
323 */
324 sk_mem_reclaim(sk);
325 }
326 EXPORT_SYMBOL_GPL(sk_clear_memalloc);
327
328 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
329 {
330 int ret;
331 unsigned long pflags = current->flags;
332
333 /* these should have been dropped before queueing */
334 BUG_ON(!sock_flag(sk, SOCK_MEMALLOC));
335
336 current->flags |= PF_MEMALLOC;
337 ret = sk->sk_backlog_rcv(sk, skb);
338 tsk_restore_flags(current, pflags, PF_MEMALLOC);
339
340 return ret;
341 }
342 EXPORT_SYMBOL(__sk_backlog_rcv);
343
344 static int sock_set_timeout(long *timeo_p, char __user *optval, int optlen)
345 {
346 struct timeval tv;
347
348 if (optlen < sizeof(tv))
349 return -EINVAL;
350 if (copy_from_user(&tv, optval, sizeof(tv)))
351 return -EFAULT;
352 if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
353 return -EDOM;
354
355 if (tv.tv_sec < 0) {
356 static int warned __read_mostly;
357
358 *timeo_p = 0;
359 if (warned < 10 && net_ratelimit()) {
360 warned++;
361 pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
362 __func__, current->comm, task_pid_nr(current));
363 }
364 return 0;
365 }
366 *timeo_p = MAX_SCHEDULE_TIMEOUT;
367 if (tv.tv_sec == 0 && tv.tv_usec == 0)
368 return 0;
369 if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT/HZ - 1))
370 *timeo_p = tv.tv_sec*HZ + (tv.tv_usec+(1000000/HZ-1))/(1000000/HZ);
371 return 0;
372 }
373
374 static void sock_warn_obsolete_bsdism(const char *name)
375 {
376 static int warned;
377 static char warncomm[TASK_COMM_LEN];
378 if (strcmp(warncomm, current->comm) && warned < 5) {
379 strcpy(warncomm, current->comm);
380 pr_warn("process `%s' is using obsolete %s SO_BSDCOMPAT\n",
381 warncomm, name);
382 warned++;
383 }
384 }
385
386 static bool sock_needs_netstamp(const struct sock *sk)
387 {
388 switch (sk->sk_family) {
389 case AF_UNSPEC:
390 case AF_UNIX:
391 return false;
392 default:
393 return true;
394 }
395 }
396
397 static void sock_disable_timestamp(struct sock *sk, unsigned long flags)
398 {
399 if (sk->sk_flags & flags) {
400 sk->sk_flags &= ~flags;
401 if (sock_needs_netstamp(sk) &&
402 !(sk->sk_flags & SK_FLAGS_TIMESTAMP))
403 net_disable_timestamp();
404 }
405 }
406
407
408 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
409 {
410 int err;
411 unsigned long flags;
412 struct sk_buff_head *list = &sk->sk_receive_queue;
413
414 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) {
415 atomic_inc(&sk->sk_drops);
416 trace_sock_rcvqueue_full(sk, skb);
417 return -ENOMEM;
418 }
419
420 err = sk_filter(sk, skb);
421 if (err)
422 return err;
423
424 if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
425 atomic_inc(&sk->sk_drops);
426 return -ENOBUFS;
427 }
428
429 skb->dev = NULL;
430 skb_set_owner_r(skb, sk);
431
432 /* we escape from rcu protected region, make sure we dont leak
433 * a norefcounted dst
434 */
435 skb_dst_force(skb);
436
437 spin_lock_irqsave(&list->lock, flags);
438 sock_skb_set_dropcount(sk, skb);
439 __skb_queue_tail(list, skb);
440 spin_unlock_irqrestore(&list->lock, flags);
441
442 if (!sock_flag(sk, SOCK_DEAD))
443 sk->sk_data_ready(sk);
444 return 0;
445 }
446 EXPORT_SYMBOL(sock_queue_rcv_skb);
447
448 int sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested)
449 {
450 int rc = NET_RX_SUCCESS;
451
452 if (sk_filter(sk, skb))
453 goto discard_and_relse;
454
455 skb->dev = NULL;
456
457 if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) {
458 atomic_inc(&sk->sk_drops);
459 goto discard_and_relse;
460 }
461 if (nested)
462 bh_lock_sock_nested(sk);
463 else
464 bh_lock_sock(sk);
465 if (!sock_owned_by_user(sk)) {
466 /*
467 * trylock + unlock semantics:
468 */
469 mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
470
471 rc = sk_backlog_rcv(sk, skb);
472
473 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
474 } else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) {
475 bh_unlock_sock(sk);
476 atomic_inc(&sk->sk_drops);
477 goto discard_and_relse;
478 }
479
480 bh_unlock_sock(sk);
481 out:
482 sock_put(sk);
483 return rc;
484 discard_and_relse:
485 kfree_skb(skb);
486 goto out;
487 }
488 EXPORT_SYMBOL(sk_receive_skb);
489
490 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
491 {
492 struct dst_entry *dst = __sk_dst_get(sk);
493
494 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
495 sk_tx_queue_clear(sk);
496 RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
497 dst_release(dst);
498 return NULL;
499 }
500
501 return dst;
502 }
503 EXPORT_SYMBOL(__sk_dst_check);
504
505 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
506 {
507 struct dst_entry *dst = sk_dst_get(sk);
508
509 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
510 sk_dst_reset(sk);
511 dst_release(dst);
512 return NULL;
513 }
514
515 return dst;
516 }
517 EXPORT_SYMBOL(sk_dst_check);
518
519 static int sock_setbindtodevice(struct sock *sk, char __user *optval,
520 int optlen)
521 {
522 int ret = -ENOPROTOOPT;
523 #ifdef CONFIG_NETDEVICES
524 struct net *net = sock_net(sk);
525 char devname[IFNAMSIZ];
526 int index;
527
528 /* Sorry... */
529 ret = -EPERM;
530 if (!ns_capable(net->user_ns, CAP_NET_RAW))
531 goto out;
532
533 ret = -EINVAL;
534 if (optlen < 0)
535 goto out;
536
537 /* Bind this socket to a particular device like "eth0",
538 * as specified in the passed interface name. If the
539 * name is "" or the option length is zero the socket
540 * is not bound.
541 */
542 if (optlen > IFNAMSIZ - 1)
543 optlen = IFNAMSIZ - 1;
544 memset(devname, 0, sizeof(devname));
545
546 ret = -EFAULT;
547 if (copy_from_user(devname, optval, optlen))
548 goto out;
549
550 index = 0;
551 if (devname[0] != '\0') {
552 struct net_device *dev;
553
554 rcu_read_lock();
555 dev = dev_get_by_name_rcu(net, devname);
556 if (dev)
557 index = dev->ifindex;
558 rcu_read_unlock();
559 ret = -ENODEV;
560 if (!dev)
561 goto out;
562 }
563
564 lock_sock(sk);
565 sk->sk_bound_dev_if = index;
566 sk_dst_reset(sk);
567 release_sock(sk);
568
569 ret = 0;
570
571 out:
572 #endif
573
574 return ret;
575 }
576
577 static int sock_getbindtodevice(struct sock *sk, char __user *optval,
578 int __user *optlen, int len)
579 {
580 int ret = -ENOPROTOOPT;
581 #ifdef CONFIG_NETDEVICES
582 struct net *net = sock_net(sk);
583 char devname[IFNAMSIZ];
584
585 if (sk->sk_bound_dev_if == 0) {
586 len = 0;
587 goto zero;
588 }
589
590 ret = -EINVAL;
591 if (len < IFNAMSIZ)
592 goto out;
593
594 ret = netdev_get_name(net, devname, sk->sk_bound_dev_if);
595 if (ret)
596 goto out;
597
598 len = strlen(devname) + 1;
599
600 ret = -EFAULT;
601 if (copy_to_user(optval, devname, len))
602 goto out;
603
604 zero:
605 ret = -EFAULT;
606 if (put_user(len, optlen))
607 goto out;
608
609 ret = 0;
610
611 out:
612 #endif
613
614 return ret;
615 }
616
617 static inline void sock_valbool_flag(struct sock *sk, int bit, int valbool)
618 {
619 if (valbool)
620 sock_set_flag(sk, bit);
621 else
622 sock_reset_flag(sk, bit);
623 }
624
625 bool sk_mc_loop(struct sock *sk)
626 {
627 if (dev_recursion_level())
628 return false;
629 if (!sk)
630 return true;
631 switch (sk->sk_family) {
632 case AF_INET:
633 return inet_sk(sk)->mc_loop;
634 #if IS_ENABLED(CONFIG_IPV6)
635 case AF_INET6:
636 return inet6_sk(sk)->mc_loop;
637 #endif
638 }
639 WARN_ON(1);
640 return true;
641 }
642 EXPORT_SYMBOL(sk_mc_loop);
643
644 /*
645 * This is meant for all protocols to use and covers goings on
646 * at the socket level. Everything here is generic.
647 */
648
649 int sock_setsockopt(struct socket *sock, int level, int optname,
650 char __user *optval, unsigned int optlen)
651 {
652 struct sock *sk = sock->sk;
653 int val;
654 int valbool;
655 struct linger ling;
656 int ret = 0;
657
658 /*
659 * Options without arguments
660 */
661
662 if (optname == SO_BINDTODEVICE)
663 return sock_setbindtodevice(sk, optval, optlen);
664
665 if (optlen < sizeof(int))
666 return -EINVAL;
667
668 if (get_user(val, (int __user *)optval))
669 return -EFAULT;
670
671 valbool = val ? 1 : 0;
672
673 lock_sock(sk);
674
675 switch (optname) {
676 case SO_DEBUG:
677 if (val && !capable(CAP_NET_ADMIN))
678 ret = -EACCES;
679 else
680 sock_valbool_flag(sk, SOCK_DBG, valbool);
681 break;
682 case SO_REUSEADDR:
683 sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
684 break;
685 case SO_REUSEPORT:
686 sk->sk_reuseport = valbool;
687 break;
688 case SO_TYPE:
689 case SO_PROTOCOL:
690 case SO_DOMAIN:
691 case SO_ERROR:
692 ret = -ENOPROTOOPT;
693 break;
694 case SO_DONTROUTE:
695 sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
696 break;
697 case SO_BROADCAST:
698 sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
699 break;
700 case SO_SNDBUF:
701 /* Don't error on this BSD doesn't and if you think
702 * about it this is right. Otherwise apps have to
703 * play 'guess the biggest size' games. RCVBUF/SNDBUF
704 * are treated in BSD as hints
705 */
706 val = min_t(u32, val, sysctl_wmem_max);
707 set_sndbuf:
708 sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
709 sk->sk_sndbuf = max_t(u32, val * 2, SOCK_MIN_SNDBUF);
710 /* Wake up sending tasks if we upped the value. */
711 sk->sk_write_space(sk);
712 break;
713
714 case SO_SNDBUFFORCE:
715 if (!capable(CAP_NET_ADMIN)) {
716 ret = -EPERM;
717 break;
718 }
719 goto set_sndbuf;
720
721 case SO_RCVBUF:
722 /* Don't error on this BSD doesn't and if you think
723 * about it this is right. Otherwise apps have to
724 * play 'guess the biggest size' games. RCVBUF/SNDBUF
725 * are treated in BSD as hints
726 */
727 val = min_t(u32, val, sysctl_rmem_max);
728 set_rcvbuf:
729 sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
730 /*
731 * We double it on the way in to account for
732 * "struct sk_buff" etc. overhead. Applications
733 * assume that the SO_RCVBUF setting they make will
734 * allow that much actual data to be received on that
735 * socket.
736 *
737 * Applications are unaware that "struct sk_buff" and
738 * other overheads allocate from the receive buffer
739 * during socket buffer allocation.
740 *
741 * And after considering the possible alternatives,
742 * returning the value we actually used in getsockopt
743 * is the most desirable behavior.
744 */
745 sk->sk_rcvbuf = max_t(u32, val * 2, SOCK_MIN_RCVBUF);
746 break;
747
748 case SO_RCVBUFFORCE:
749 if (!capable(CAP_NET_ADMIN)) {
750 ret = -EPERM;
751 break;
752 }
753 goto set_rcvbuf;
754
755 case SO_KEEPALIVE:
756 #ifdef CONFIG_INET
757 if (sk->sk_protocol == IPPROTO_TCP &&
758 sk->sk_type == SOCK_STREAM)
759 tcp_set_keepalive(sk, valbool);
760 #endif
761 sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
762 break;
763
764 case SO_OOBINLINE:
765 sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
766 break;
767
768 case SO_NO_CHECK:
769 sk->sk_no_check_tx = valbool;
770 break;
771
772 case SO_PRIORITY:
773 if ((val >= 0 && val <= 6) ||
774 ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
775 sk->sk_priority = val;
776 else
777 ret = -EPERM;
778 break;
779
780 case SO_LINGER:
781 if (optlen < sizeof(ling)) {
782 ret = -EINVAL; /* 1003.1g */
783 break;
784 }
785 if (copy_from_user(&ling, optval, sizeof(ling))) {
786 ret = -EFAULT;
787 break;
788 }
789 if (!ling.l_onoff)
790 sock_reset_flag(sk, SOCK_LINGER);
791 else {
792 #if (BITS_PER_LONG == 32)
793 if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
794 sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT;
795 else
796 #endif
797 sk->sk_lingertime = (unsigned int)ling.l_linger * HZ;
798 sock_set_flag(sk, SOCK_LINGER);
799 }
800 break;
801
802 case SO_BSDCOMPAT:
803 sock_warn_obsolete_bsdism("setsockopt");
804 break;
805
806 case SO_PASSCRED:
807 if (valbool)
808 set_bit(SOCK_PASSCRED, &sock->flags);
809 else
810 clear_bit(SOCK_PASSCRED, &sock->flags);
811 break;
812
813 case SO_TIMESTAMP:
814 case SO_TIMESTAMPNS:
815 if (valbool) {
816 if (optname == SO_TIMESTAMP)
817 sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
818 else
819 sock_set_flag(sk, SOCK_RCVTSTAMPNS);
820 sock_set_flag(sk, SOCK_RCVTSTAMP);
821 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
822 } else {
823 sock_reset_flag(sk, SOCK_RCVTSTAMP);
824 sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
825 }
826 break;
827
828 case SO_TIMESTAMPING:
829 if (val & ~SOF_TIMESTAMPING_MASK) {
830 ret = -EINVAL;
831 break;
832 }
833
834 if (val & SOF_TIMESTAMPING_OPT_ID &&
835 !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) {
836 if (sk->sk_protocol == IPPROTO_TCP &&
837 sk->sk_type == SOCK_STREAM) {
838 if (sk->sk_state != TCP_ESTABLISHED) {
839 ret = -EINVAL;
840 break;
841 }
842 sk->sk_tskey = tcp_sk(sk)->snd_una;
843 } else {
844 sk->sk_tskey = 0;
845 }
846 }
847 sk->sk_tsflags = val;
848 if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
849 sock_enable_timestamp(sk,
850 SOCK_TIMESTAMPING_RX_SOFTWARE);
851 else
852 sock_disable_timestamp(sk,
853 (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
854 break;
855
856 case SO_RCVLOWAT:
857 if (val < 0)
858 val = INT_MAX;
859 sk->sk_rcvlowat = val ? : 1;
860 break;
861
862 case SO_RCVTIMEO:
863 ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, optlen);
864 break;
865
866 case SO_SNDTIMEO:
867 ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen);
868 break;
869
870 case SO_ATTACH_FILTER:
871 ret = -EINVAL;
872 if (optlen == sizeof(struct sock_fprog)) {
873 struct sock_fprog fprog;
874
875 ret = -EFAULT;
876 if (copy_from_user(&fprog, optval, sizeof(fprog)))
877 break;
878
879 ret = sk_attach_filter(&fprog, sk);
880 }
881 break;
882
883 case SO_ATTACH_BPF:
884 ret = -EINVAL;
885 if (optlen == sizeof(u32)) {
886 u32 ufd;
887
888 ret = -EFAULT;
889 if (copy_from_user(&ufd, optval, sizeof(ufd)))
890 break;
891
892 ret = sk_attach_bpf(ufd, sk);
893 }
894 break;
895
896 case SO_ATTACH_REUSEPORT_CBPF:
897 ret = -EINVAL;
898 if (optlen == sizeof(struct sock_fprog)) {
899 struct sock_fprog fprog;
900
901 ret = -EFAULT;
902 if (copy_from_user(&fprog, optval, sizeof(fprog)))
903 break;
904
905 ret = sk_reuseport_attach_filter(&fprog, sk);
906 }
907 break;
908
909 case SO_ATTACH_REUSEPORT_EBPF:
910 ret = -EINVAL;
911 if (optlen == sizeof(u32)) {
912 u32 ufd;
913
914 ret = -EFAULT;
915 if (copy_from_user(&ufd, optval, sizeof(ufd)))
916 break;
917
918 ret = sk_reuseport_attach_bpf(ufd, sk);
919 }
920 break;
921
922 case SO_DETACH_FILTER:
923 ret = sk_detach_filter(sk);
924 break;
925
926 case SO_LOCK_FILTER:
927 if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool)
928 ret = -EPERM;
929 else
930 sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool);
931 break;
932
933 case SO_PASSSEC:
934 if (valbool)
935 set_bit(SOCK_PASSSEC, &sock->flags);
936 else
937 clear_bit(SOCK_PASSSEC, &sock->flags);
938 break;
939 case SO_MARK:
940 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
941 ret = -EPERM;
942 else
943 sk->sk_mark = val;
944 break;
945
946 case SO_RXQ_OVFL:
947 sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
948 break;
949
950 case SO_WIFI_STATUS:
951 sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
952 break;
953
954 case SO_PEEK_OFF:
955 if (sock->ops->set_peek_off)
956 ret = sock->ops->set_peek_off(sk, val);
957 else
958 ret = -EOPNOTSUPP;
959 break;
960
961 case SO_NOFCS:
962 sock_valbool_flag(sk, SOCK_NOFCS, valbool);
963 break;
964
965 case SO_SELECT_ERR_QUEUE:
966 sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
967 break;
968
969 #ifdef CONFIG_NET_RX_BUSY_POLL
970 case SO_BUSY_POLL:
971 /* allow unprivileged users to decrease the value */
972 if ((val > sk->sk_ll_usec) && !capable(CAP_NET_ADMIN))
973 ret = -EPERM;
974 else {
975 if (val < 0)
976 ret = -EINVAL;
977 else
978 sk->sk_ll_usec = val;
979 }
980 break;
981 #endif
982
983 case SO_MAX_PACING_RATE:
984 sk->sk_max_pacing_rate = val;
985 sk->sk_pacing_rate = min(sk->sk_pacing_rate,
986 sk->sk_max_pacing_rate);
987 break;
988
989 case SO_INCOMING_CPU:
990 sk->sk_incoming_cpu = val;
991 break;
992
993 case SO_CNX_ADVICE:
994 if (val == 1)
995 dst_negative_advice(sk);
996 break;
997 default:
998 ret = -ENOPROTOOPT;
999 break;
1000 }
1001 release_sock(sk);
1002 return ret;
1003 }
1004 EXPORT_SYMBOL(sock_setsockopt);
1005
1006
1007 static void cred_to_ucred(struct pid *pid, const struct cred *cred,
1008 struct ucred *ucred)
1009 {
1010 ucred->pid = pid_vnr(pid);
1011 ucred->uid = ucred->gid = -1;
1012 if (cred) {
1013 struct user_namespace *current_ns = current_user_ns();
1014
1015 ucred->uid = from_kuid_munged(current_ns, cred->euid);
1016 ucred->gid = from_kgid_munged(current_ns, cred->egid);
1017 }
1018 }
1019
1020 int sock_getsockopt(struct socket *sock, int level, int optname,
1021 char __user *optval, int __user *optlen)
1022 {
1023 struct sock *sk = sock->sk;
1024
1025 union {
1026 int val;
1027 struct linger ling;
1028 struct timeval tm;
1029 } v;
1030
1031 int lv = sizeof(int);
1032 int len;
1033
1034 if (get_user(len, optlen))
1035 return -EFAULT;
1036 if (len < 0)
1037 return -EINVAL;
1038
1039 memset(&v, 0, sizeof(v));
1040
1041 switch (optname) {
1042 case SO_DEBUG:
1043 v.val = sock_flag(sk, SOCK_DBG);
1044 break;
1045
1046 case SO_DONTROUTE:
1047 v.val = sock_flag(sk, SOCK_LOCALROUTE);
1048 break;
1049
1050 case SO_BROADCAST:
1051 v.val = sock_flag(sk, SOCK_BROADCAST);
1052 break;
1053
1054 case SO_SNDBUF:
1055 v.val = sk->sk_sndbuf;
1056 break;
1057
1058 case SO_RCVBUF:
1059 v.val = sk->sk_rcvbuf;
1060 break;
1061
1062 case SO_REUSEADDR:
1063 v.val = sk->sk_reuse;
1064 break;
1065
1066 case SO_REUSEPORT:
1067 v.val = sk->sk_reuseport;
1068 break;
1069
1070 case SO_KEEPALIVE:
1071 v.val = sock_flag(sk, SOCK_KEEPOPEN);
1072 break;
1073
1074 case SO_TYPE:
1075 v.val = sk->sk_type;
1076 break;
1077
1078 case SO_PROTOCOL:
1079 v.val = sk->sk_protocol;
1080 break;
1081
1082 case SO_DOMAIN:
1083 v.val = sk->sk_family;
1084 break;
1085
1086 case SO_ERROR:
1087 v.val = -sock_error(sk);
1088 if (v.val == 0)
1089 v.val = xchg(&sk->sk_err_soft, 0);
1090 break;
1091
1092 case SO_OOBINLINE:
1093 v.val = sock_flag(sk, SOCK_URGINLINE);
1094 break;
1095
1096 case SO_NO_CHECK:
1097 v.val = sk->sk_no_check_tx;
1098 break;
1099
1100 case SO_PRIORITY:
1101 v.val = sk->sk_priority;
1102 break;
1103
1104 case SO_LINGER:
1105 lv = sizeof(v.ling);
1106 v.ling.l_onoff = sock_flag(sk, SOCK_LINGER);
1107 v.ling.l_linger = sk->sk_lingertime / HZ;
1108 break;
1109
1110 case SO_BSDCOMPAT:
1111 sock_warn_obsolete_bsdism("getsockopt");
1112 break;
1113
1114 case SO_TIMESTAMP:
1115 v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
1116 !sock_flag(sk, SOCK_RCVTSTAMPNS);
1117 break;
1118
1119 case SO_TIMESTAMPNS:
1120 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS);
1121 break;
1122
1123 case SO_TIMESTAMPING:
1124 v.val = sk->sk_tsflags;
1125 break;
1126
1127 case SO_RCVTIMEO:
1128 lv = sizeof(struct timeval);
1129 if (sk->sk_rcvtimeo == MAX_SCHEDULE_TIMEOUT) {
1130 v.tm.tv_sec = 0;
1131 v.tm.tv_usec = 0;
1132 } else {
1133 v.tm.tv_sec = sk->sk_rcvtimeo / HZ;
1134 v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * 1000000) / HZ;
1135 }
1136 break;
1137
1138 case SO_SNDTIMEO:
1139 lv = sizeof(struct timeval);
1140 if (sk->sk_sndtimeo == MAX_SCHEDULE_TIMEOUT) {
1141 v.tm.tv_sec = 0;
1142 v.tm.tv_usec = 0;
1143 } else {
1144 v.tm.tv_sec = sk->sk_sndtimeo / HZ;
1145 v.tm.tv_usec = ((sk->sk_sndtimeo % HZ) * 1000000) / HZ;
1146 }
1147 break;
1148
1149 case SO_RCVLOWAT:
1150 v.val = sk->sk_rcvlowat;
1151 break;
1152
1153 case SO_SNDLOWAT:
1154 v.val = 1;
1155 break;
1156
1157 case SO_PASSCRED:
1158 v.val = !!test_bit(SOCK_PASSCRED, &sock->flags);
1159 break;
1160
1161 case SO_PEERCRED:
1162 {
1163 struct ucred peercred;
1164 if (len > sizeof(peercred))
1165 len = sizeof(peercred);
1166 cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1167 if (copy_to_user(optval, &peercred, len))
1168 return -EFAULT;
1169 goto lenout;
1170 }
1171
1172 case SO_PEERNAME:
1173 {
1174 char address[128];
1175
1176 if (sock->ops->getname(sock, (struct sockaddr *)address, &lv, 2))
1177 return -ENOTCONN;
1178 if (lv < len)
1179 return -EINVAL;
1180 if (copy_to_user(optval, address, len))
1181 return -EFAULT;
1182 goto lenout;
1183 }
1184
1185 /* Dubious BSD thing... Probably nobody even uses it, but
1186 * the UNIX standard wants it for whatever reason... -DaveM
1187 */
1188 case SO_ACCEPTCONN:
1189 v.val = sk->sk_state == TCP_LISTEN;
1190 break;
1191
1192 case SO_PASSSEC:
1193 v.val = !!test_bit(SOCK_PASSSEC, &sock->flags);
1194 break;
1195
1196 case SO_PEERSEC:
1197 return security_socket_getpeersec_stream(sock, optval, optlen, len);
1198
1199 case SO_MARK:
1200 v.val = sk->sk_mark;
1201 break;
1202
1203 case SO_RXQ_OVFL:
1204 v.val = sock_flag(sk, SOCK_RXQ_OVFL);
1205 break;
1206
1207 case SO_WIFI_STATUS:
1208 v.val = sock_flag(sk, SOCK_WIFI_STATUS);
1209 break;
1210
1211 case SO_PEEK_OFF:
1212 if (!sock->ops->set_peek_off)
1213 return -EOPNOTSUPP;
1214
1215 v.val = sk->sk_peek_off;
1216 break;
1217 case SO_NOFCS:
1218 v.val = sock_flag(sk, SOCK_NOFCS);
1219 break;
1220
1221 case SO_BINDTODEVICE:
1222 return sock_getbindtodevice(sk, optval, optlen, len);
1223
1224 case SO_GET_FILTER:
1225 len = sk_get_filter(sk, (struct sock_filter __user *)optval, len);
1226 if (len < 0)
1227 return len;
1228
1229 goto lenout;
1230
1231 case SO_LOCK_FILTER:
1232 v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
1233 break;
1234
1235 case SO_BPF_EXTENSIONS:
1236 v.val = bpf_tell_extensions();
1237 break;
1238
1239 case SO_SELECT_ERR_QUEUE:
1240 v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
1241 break;
1242
1243 #ifdef CONFIG_NET_RX_BUSY_POLL
1244 case SO_BUSY_POLL:
1245 v.val = sk->sk_ll_usec;
1246 break;
1247 #endif
1248
1249 case SO_MAX_PACING_RATE:
1250 v.val = sk->sk_max_pacing_rate;
1251 break;
1252
1253 case SO_INCOMING_CPU:
1254 v.val = sk->sk_incoming_cpu;
1255 break;
1256
1257 default:
1258 /* We implement the SO_SNDLOWAT etc to not be settable
1259 * (1003.1g 7).
1260 */
1261 return -ENOPROTOOPT;
1262 }
1263
1264 if (len > lv)
1265 len = lv;
1266 if (copy_to_user(optval, &v, len))
1267 return -EFAULT;
1268 lenout:
1269 if (put_user(len, optlen))
1270 return -EFAULT;
1271 return 0;
1272 }
1273
1274 /*
1275 * Initialize an sk_lock.
1276 *
1277 * (We also register the sk_lock with the lock validator.)
1278 */
1279 static inline void sock_lock_init(struct sock *sk)
1280 {
1281 sock_lock_init_class_and_name(sk,
1282 af_family_slock_key_strings[sk->sk_family],
1283 af_family_slock_keys + sk->sk_family,
1284 af_family_key_strings[sk->sk_family],
1285 af_family_keys + sk->sk_family);
1286 }
1287
1288 /*
1289 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
1290 * even temporarly, because of RCU lookups. sk_node should also be left as is.
1291 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
1292 */
1293 static void sock_copy(struct sock *nsk, const struct sock *osk)
1294 {
1295 #ifdef CONFIG_SECURITY_NETWORK
1296 void *sptr = nsk->sk_security;
1297 #endif
1298 memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
1299
1300 memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
1301 osk->sk_prot->obj_size - offsetof(struct sock, sk_dontcopy_end));
1302
1303 #ifdef CONFIG_SECURITY_NETWORK
1304 nsk->sk_security = sptr;
1305 security_sk_clone(osk, nsk);
1306 #endif
1307 }
1308
1309 void sk_prot_clear_portaddr_nulls(struct sock *sk, int size)
1310 {
1311 unsigned long nulls1, nulls2;
1312
1313 nulls1 = offsetof(struct sock, __sk_common.skc_node.next);
1314 nulls2 = offsetof(struct sock, __sk_common.skc_portaddr_node.next);
1315 if (nulls1 > nulls2)
1316 swap(nulls1, nulls2);
1317
1318 if (nulls1 != 0)
1319 memset((char *)sk, 0, nulls1);
1320 memset((char *)sk + nulls1 + sizeof(void *), 0,
1321 nulls2 - nulls1 - sizeof(void *));
1322 memset((char *)sk + nulls2 + sizeof(void *), 0,
1323 size - nulls2 - sizeof(void *));
1324 }
1325 EXPORT_SYMBOL(sk_prot_clear_portaddr_nulls);
1326
1327 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
1328 int family)
1329 {
1330 struct sock *sk;
1331 struct kmem_cache *slab;
1332
1333 slab = prot->slab;
1334 if (slab != NULL) {
1335 sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
1336 if (!sk)
1337 return sk;
1338 if (priority & __GFP_ZERO) {
1339 if (prot->clear_sk)
1340 prot->clear_sk(sk, prot->obj_size);
1341 else
1342 sk_prot_clear_nulls(sk, prot->obj_size);
1343 }
1344 } else
1345 sk = kmalloc(prot->obj_size, priority);
1346
1347 if (sk != NULL) {
1348 kmemcheck_annotate_bitfield(sk, flags);
1349
1350 if (security_sk_alloc(sk, family, priority))
1351 goto out_free;
1352
1353 if (!try_module_get(prot->owner))
1354 goto out_free_sec;
1355 sk_tx_queue_clear(sk);
1356 cgroup_sk_alloc(&sk->sk_cgrp_data);
1357 }
1358
1359 return sk;
1360
1361 out_free_sec:
1362 security_sk_free(sk);
1363 out_free:
1364 if (slab != NULL)
1365 kmem_cache_free(slab, sk);
1366 else
1367 kfree(sk);
1368 return NULL;
1369 }
1370
1371 static void sk_prot_free(struct proto *prot, struct sock *sk)
1372 {
1373 struct kmem_cache *slab;
1374 struct module *owner;
1375
1376 owner = prot->owner;
1377 slab = prot->slab;
1378
1379 cgroup_sk_free(&sk->sk_cgrp_data);
1380 security_sk_free(sk);
1381 if (slab != NULL)
1382 kmem_cache_free(slab, sk);
1383 else
1384 kfree(sk);
1385 module_put(owner);
1386 }
1387
1388 /**
1389 * sk_alloc - All socket objects are allocated here
1390 * @net: the applicable net namespace
1391 * @family: protocol family
1392 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1393 * @prot: struct proto associated with this new sock instance
1394 * @kern: is this to be a kernel socket?
1395 */
1396 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1397 struct proto *prot, int kern)
1398 {
1399 struct sock *sk;
1400
1401 sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
1402 if (sk) {
1403 sk->sk_family = family;
1404 /*
1405 * See comment in struct sock definition to understand
1406 * why we need sk_prot_creator -acme
1407 */
1408 sk->sk_prot = sk->sk_prot_creator = prot;
1409 sock_lock_init(sk);
1410 sk->sk_net_refcnt = kern ? 0 : 1;
1411 if (likely(sk->sk_net_refcnt))
1412 get_net(net);
1413 sock_net_set(sk, net);
1414 atomic_set(&sk->sk_wmem_alloc, 1);
1415
1416 sock_update_classid(&sk->sk_cgrp_data);
1417 sock_update_netprioidx(&sk->sk_cgrp_data);
1418 }
1419
1420 return sk;
1421 }
1422 EXPORT_SYMBOL(sk_alloc);
1423
1424 void sk_destruct(struct sock *sk)
1425 {
1426 struct sk_filter *filter;
1427
1428 if (sk->sk_destruct)
1429 sk->sk_destruct(sk);
1430
1431 filter = rcu_dereference_check(sk->sk_filter,
1432 atomic_read(&sk->sk_wmem_alloc) == 0);
1433 if (filter) {
1434 sk_filter_uncharge(sk, filter);
1435 RCU_INIT_POINTER(sk->sk_filter, NULL);
1436 }
1437 if (rcu_access_pointer(sk->sk_reuseport_cb))
1438 reuseport_detach_sock(sk);
1439
1440 sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
1441
1442 if (atomic_read(&sk->sk_omem_alloc))
1443 pr_debug("%s: optmem leakage (%d bytes) detected\n",
1444 __func__, atomic_read(&sk->sk_omem_alloc));
1445
1446 if (sk->sk_peer_cred)
1447 put_cred(sk->sk_peer_cred);
1448 put_pid(sk->sk_peer_pid);
1449 if (likely(sk->sk_net_refcnt))
1450 put_net(sock_net(sk));
1451 sk_prot_free(sk->sk_prot_creator, sk);
1452 }
1453
1454 static void __sk_free(struct sock *sk)
1455 {
1456 if (unlikely(sock_diag_has_destroy_listeners(sk) && sk->sk_net_refcnt))
1457 sock_diag_broadcast_destroy(sk);
1458 else
1459 sk_destruct(sk);
1460 }
1461
1462 void sk_free(struct sock *sk)
1463 {
1464 /*
1465 * We subtract one from sk_wmem_alloc and can know if
1466 * some packets are still in some tx queue.
1467 * If not null, sock_wfree() will call __sk_free(sk) later
1468 */
1469 if (atomic_dec_and_test(&sk->sk_wmem_alloc))
1470 __sk_free(sk);
1471 }
1472 EXPORT_SYMBOL(sk_free);
1473
1474 /**
1475 * sk_clone_lock - clone a socket, and lock its clone
1476 * @sk: the socket to clone
1477 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1478 *
1479 * Caller must unlock socket even in error path (bh_unlock_sock(newsk))
1480 */
1481 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
1482 {
1483 struct sock *newsk;
1484 bool is_charged = true;
1485
1486 newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family);
1487 if (newsk != NULL) {
1488 struct sk_filter *filter;
1489
1490 sock_copy(newsk, sk);
1491
1492 /* SANITY */
1493 if (likely(newsk->sk_net_refcnt))
1494 get_net(sock_net(newsk));
1495 sk_node_init(&newsk->sk_node);
1496 sock_lock_init(newsk);
1497 bh_lock_sock(newsk);
1498 newsk->sk_backlog.head = newsk->sk_backlog.tail = NULL;
1499 newsk->sk_backlog.len = 0;
1500
1501 atomic_set(&newsk->sk_rmem_alloc, 0);
1502 /*
1503 * sk_wmem_alloc set to one (see sk_free() and sock_wfree())
1504 */
1505 atomic_set(&newsk->sk_wmem_alloc, 1);
1506 atomic_set(&newsk->sk_omem_alloc, 0);
1507 skb_queue_head_init(&newsk->sk_receive_queue);
1508 skb_queue_head_init(&newsk->sk_write_queue);
1509
1510 rwlock_init(&newsk->sk_callback_lock);
1511 lockdep_set_class_and_name(&newsk->sk_callback_lock,
1512 af_callback_keys + newsk->sk_family,
1513 af_family_clock_key_strings[newsk->sk_family]);
1514
1515 newsk->sk_dst_cache = NULL;
1516 newsk->sk_wmem_queued = 0;
1517 newsk->sk_forward_alloc = 0;
1518 newsk->sk_send_head = NULL;
1519 newsk->sk_userlocks = sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
1520
1521 sock_reset_flag(newsk, SOCK_DONE);
1522 skb_queue_head_init(&newsk->sk_error_queue);
1523
1524 filter = rcu_dereference_protected(newsk->sk_filter, 1);
1525 if (filter != NULL)
1526 /* though it's an empty new sock, the charging may fail
1527 * if sysctl_optmem_max was changed between creation of
1528 * original socket and cloning
1529 */
1530 is_charged = sk_filter_charge(newsk, filter);
1531
1532 if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) {
1533 /* It is still raw copy of parent, so invalidate
1534 * destructor and make plain sk_free() */
1535 newsk->sk_destruct = NULL;
1536 bh_unlock_sock(newsk);
1537 sk_free(newsk);
1538 newsk = NULL;
1539 goto out;
1540 }
1541 RCU_INIT_POINTER(newsk->sk_reuseport_cb, NULL);
1542
1543 newsk->sk_err = 0;
1544 newsk->sk_priority = 0;
1545 newsk->sk_incoming_cpu = raw_smp_processor_id();
1546 atomic64_set(&newsk->sk_cookie, 0);
1547 /*
1548 * Before updating sk_refcnt, we must commit prior changes to memory
1549 * (Documentation/RCU/rculist_nulls.txt for details)
1550 */
1551 smp_wmb();
1552 atomic_set(&newsk->sk_refcnt, 2);
1553
1554 /*
1555 * Increment the counter in the same struct proto as the master
1556 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
1557 * is the same as sk->sk_prot->socks, as this field was copied
1558 * with memcpy).
1559 *
1560 * This _changes_ the previous behaviour, where
1561 * tcp_create_openreq_child always was incrementing the
1562 * equivalent to tcp_prot->socks (inet_sock_nr), so this have
1563 * to be taken into account in all callers. -acme
1564 */
1565 sk_refcnt_debug_inc(newsk);
1566 sk_set_socket(newsk, NULL);
1567 newsk->sk_wq = NULL;
1568
1569 if (mem_cgroup_sockets_enabled && sk->sk_memcg)
1570 sock_update_memcg(newsk);
1571
1572 if (newsk->sk_prot->sockets_allocated)
1573 sk_sockets_allocated_inc(newsk);
1574
1575 if (sock_needs_netstamp(sk) &&
1576 newsk->sk_flags & SK_FLAGS_TIMESTAMP)
1577 net_enable_timestamp();
1578 }
1579 out:
1580 return newsk;
1581 }
1582 EXPORT_SYMBOL_GPL(sk_clone_lock);
1583
1584 void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
1585 {
1586 u32 max_segs = 1;
1587
1588 sk_dst_set(sk, dst);
1589 sk->sk_route_caps = dst->dev->features;
1590 if (sk->sk_route_caps & NETIF_F_GSO)
1591 sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
1592 sk->sk_route_caps &= ~sk->sk_route_nocaps;
1593 if (sk_can_gso(sk)) {
1594 if (dst->header_len) {
1595 sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
1596 } else {
1597 sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
1598 sk->sk_gso_max_size = dst->dev->gso_max_size;
1599 max_segs = max_t(u32, dst->dev->gso_max_segs, 1);
1600 }
1601 }
1602 sk->sk_gso_max_segs = max_segs;
1603 }
1604 EXPORT_SYMBOL_GPL(sk_setup_caps);
1605
1606 /*
1607 * Simple resource managers for sockets.
1608 */
1609
1610
1611 /*
1612 * Write buffer destructor automatically called from kfree_skb.
1613 */
1614 void sock_wfree(struct sk_buff *skb)
1615 {
1616 struct sock *sk = skb->sk;
1617 unsigned int len = skb->truesize;
1618
1619 if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
1620 /*
1621 * Keep a reference on sk_wmem_alloc, this will be released
1622 * after sk_write_space() call
1623 */
1624 atomic_sub(len - 1, &sk->sk_wmem_alloc);
1625 sk->sk_write_space(sk);
1626 len = 1;
1627 }
1628 /*
1629 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
1630 * could not do because of in-flight packets
1631 */
1632 if (atomic_sub_and_test(len, &sk->sk_wmem_alloc))
1633 __sk_free(sk);
1634 }
1635 EXPORT_SYMBOL(sock_wfree);
1636
1637 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
1638 {
1639 skb_orphan(skb);
1640 skb->sk = sk;
1641 #ifdef CONFIG_INET
1642 if (unlikely(!sk_fullsock(sk))) {
1643 skb->destructor = sock_edemux;
1644 sock_hold(sk);
1645 return;
1646 }
1647 #endif
1648 skb->destructor = sock_wfree;
1649 skb_set_hash_from_sk(skb, sk);
1650 /*
1651 * We used to take a refcount on sk, but following operation
1652 * is enough to guarantee sk_free() wont free this sock until
1653 * all in-flight packets are completed
1654 */
1655 atomic_add(skb->truesize, &sk->sk_wmem_alloc);
1656 }
1657 EXPORT_SYMBOL(skb_set_owner_w);
1658
1659 void skb_orphan_partial(struct sk_buff *skb)
1660 {
1661 /* TCP stack sets skb->ooo_okay based on sk_wmem_alloc,
1662 * so we do not completely orphan skb, but transfert all
1663 * accounted bytes but one, to avoid unexpected reorders.
1664 */
1665 if (skb->destructor == sock_wfree
1666 #ifdef CONFIG_INET
1667 || skb->destructor == tcp_wfree
1668 #endif
1669 ) {
1670 atomic_sub(skb->truesize - 1, &skb->sk->sk_wmem_alloc);
1671 skb->truesize = 1;
1672 } else {
1673 skb_orphan(skb);
1674 }
1675 }
1676 EXPORT_SYMBOL(skb_orphan_partial);
1677
1678 /*
1679 * Read buffer destructor automatically called from kfree_skb.
1680 */
1681 void sock_rfree(struct sk_buff *skb)
1682 {
1683 struct sock *sk = skb->sk;
1684 unsigned int len = skb->truesize;
1685
1686 atomic_sub(len, &sk->sk_rmem_alloc);
1687 sk_mem_uncharge(sk, len);
1688 }
1689 EXPORT_SYMBOL(sock_rfree);
1690
1691 /*
1692 * Buffer destructor for skbs that are not used directly in read or write
1693 * path, e.g. for error handler skbs. Automatically called from kfree_skb.
1694 */
1695 void sock_efree(struct sk_buff *skb)
1696 {
1697 sock_put(skb->sk);
1698 }
1699 EXPORT_SYMBOL(sock_efree);
1700
1701 kuid_t sock_i_uid(struct sock *sk)
1702 {
1703 kuid_t uid;
1704
1705 read_lock_bh(&sk->sk_callback_lock);
1706 uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID;
1707 read_unlock_bh(&sk->sk_callback_lock);
1708 return uid;
1709 }
1710 EXPORT_SYMBOL(sock_i_uid);
1711
1712 unsigned long sock_i_ino(struct sock *sk)
1713 {
1714 unsigned long ino;
1715
1716 read_lock_bh(&sk->sk_callback_lock);
1717 ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
1718 read_unlock_bh(&sk->sk_callback_lock);
1719 return ino;
1720 }
1721 EXPORT_SYMBOL(sock_i_ino);
1722
1723 /*
1724 * Allocate a skb from the socket's send buffer.
1725 */
1726 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1727 gfp_t priority)
1728 {
1729 if (force || atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
1730 struct sk_buff *skb = alloc_skb(size, priority);
1731 if (skb) {
1732 skb_set_owner_w(skb, sk);
1733 return skb;
1734 }
1735 }
1736 return NULL;
1737 }
1738 EXPORT_SYMBOL(sock_wmalloc);
1739
1740 /*
1741 * Allocate a memory block from the socket's option memory buffer.
1742 */
1743 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
1744 {
1745 if ((unsigned int)size <= sysctl_optmem_max &&
1746 atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) {
1747 void *mem;
1748 /* First do the add, to avoid the race if kmalloc
1749 * might sleep.
1750 */
1751 atomic_add(size, &sk->sk_omem_alloc);
1752 mem = kmalloc(size, priority);
1753 if (mem)
1754 return mem;
1755 atomic_sub(size, &sk->sk_omem_alloc);
1756 }
1757 return NULL;
1758 }
1759 EXPORT_SYMBOL(sock_kmalloc);
1760
1761 /* Free an option memory block. Note, we actually want the inline
1762 * here as this allows gcc to detect the nullify and fold away the
1763 * condition entirely.
1764 */
1765 static inline void __sock_kfree_s(struct sock *sk, void *mem, int size,
1766 const bool nullify)
1767 {
1768 if (WARN_ON_ONCE(!mem))
1769 return;
1770 if (nullify)
1771 kzfree(mem);
1772 else
1773 kfree(mem);
1774 atomic_sub(size, &sk->sk_omem_alloc);
1775 }
1776
1777 void sock_kfree_s(struct sock *sk, void *mem, int size)
1778 {
1779 __sock_kfree_s(sk, mem, size, false);
1780 }
1781 EXPORT_SYMBOL(sock_kfree_s);
1782
1783 void sock_kzfree_s(struct sock *sk, void *mem, int size)
1784 {
1785 __sock_kfree_s(sk, mem, size, true);
1786 }
1787 EXPORT_SYMBOL(sock_kzfree_s);
1788
1789 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
1790 I think, these locks should be removed for datagram sockets.
1791 */
1792 static long sock_wait_for_wmem(struct sock *sk, long timeo)
1793 {
1794 DEFINE_WAIT(wait);
1795
1796 sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
1797 for (;;) {
1798 if (!timeo)
1799 break;
1800 if (signal_pending(current))
1801 break;
1802 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1803 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1804 if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf)
1805 break;
1806 if (sk->sk_shutdown & SEND_SHUTDOWN)
1807 break;
1808 if (sk->sk_err)
1809 break;
1810 timeo = schedule_timeout(timeo);
1811 }
1812 finish_wait(sk_sleep(sk), &wait);
1813 return timeo;
1814 }
1815
1816
1817 /*
1818 * Generic send/receive buffer handlers
1819 */
1820
1821 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1822 unsigned long data_len, int noblock,
1823 int *errcode, int max_page_order)
1824 {
1825 struct sk_buff *skb;
1826 long timeo;
1827 int err;
1828
1829 timeo = sock_sndtimeo(sk, noblock);
1830 for (;;) {
1831 err = sock_error(sk);
1832 if (err != 0)
1833 goto failure;
1834
1835 err = -EPIPE;
1836 if (sk->sk_shutdown & SEND_SHUTDOWN)
1837 goto failure;
1838
1839 if (sk_wmem_alloc_get(sk) < sk->sk_sndbuf)
1840 break;
1841
1842 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
1843 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1844 err = -EAGAIN;
1845 if (!timeo)
1846 goto failure;
1847 if (signal_pending(current))
1848 goto interrupted;
1849 timeo = sock_wait_for_wmem(sk, timeo);
1850 }
1851 skb = alloc_skb_with_frags(header_len, data_len, max_page_order,
1852 errcode, sk->sk_allocation);
1853 if (skb)
1854 skb_set_owner_w(skb, sk);
1855 return skb;
1856
1857 interrupted:
1858 err = sock_intr_errno(timeo);
1859 failure:
1860 *errcode = err;
1861 return NULL;
1862 }
1863 EXPORT_SYMBOL(sock_alloc_send_pskb);
1864
1865 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
1866 int noblock, int *errcode)
1867 {
1868 return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0);
1869 }
1870 EXPORT_SYMBOL(sock_alloc_send_skb);
1871
1872 int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
1873 struct sockcm_cookie *sockc)
1874 {
1875 struct cmsghdr *cmsg;
1876
1877 for_each_cmsghdr(cmsg, msg) {
1878 if (!CMSG_OK(msg, cmsg))
1879 return -EINVAL;
1880 if (cmsg->cmsg_level != SOL_SOCKET)
1881 continue;
1882 switch (cmsg->cmsg_type) {
1883 case SO_MARK:
1884 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
1885 return -EPERM;
1886 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
1887 return -EINVAL;
1888 sockc->mark = *(u32 *)CMSG_DATA(cmsg);
1889 break;
1890 default:
1891 return -EINVAL;
1892 }
1893 }
1894 return 0;
1895 }
1896 EXPORT_SYMBOL(sock_cmsg_send);
1897
1898 /* On 32bit arches, an skb frag is limited to 2^15 */
1899 #define SKB_FRAG_PAGE_ORDER get_order(32768)
1900
1901 /**
1902 * skb_page_frag_refill - check that a page_frag contains enough room
1903 * @sz: minimum size of the fragment we want to get
1904 * @pfrag: pointer to page_frag
1905 * @gfp: priority for memory allocation
1906 *
1907 * Note: While this allocator tries to use high order pages, there is
1908 * no guarantee that allocations succeed. Therefore, @sz MUST be
1909 * less or equal than PAGE_SIZE.
1910 */
1911 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp)
1912 {
1913 if (pfrag->page) {
1914 if (page_ref_count(pfrag->page) == 1) {
1915 pfrag->offset = 0;
1916 return true;
1917 }
1918 if (pfrag->offset + sz <= pfrag->size)
1919 return true;
1920 put_page(pfrag->page);
1921 }
1922
1923 pfrag->offset = 0;
1924 if (SKB_FRAG_PAGE_ORDER) {
1925 /* Avoid direct reclaim but allow kswapd to wake */
1926 pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) |
1927 __GFP_COMP | __GFP_NOWARN |
1928 __GFP_NORETRY,
1929 SKB_FRAG_PAGE_ORDER);
1930 if (likely(pfrag->page)) {
1931 pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
1932 return true;
1933 }
1934 }
1935 pfrag->page = alloc_page(gfp);
1936 if (likely(pfrag->page)) {
1937 pfrag->size = PAGE_SIZE;
1938 return true;
1939 }
1940 return false;
1941 }
1942 EXPORT_SYMBOL(skb_page_frag_refill);
1943
1944 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
1945 {
1946 if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
1947 return true;
1948
1949 sk_enter_memory_pressure(sk);
1950 sk_stream_moderate_sndbuf(sk);
1951 return false;
1952 }
1953 EXPORT_SYMBOL(sk_page_frag_refill);
1954
1955 static void __lock_sock(struct sock *sk)
1956 __releases(&sk->sk_lock.slock)
1957 __acquires(&sk->sk_lock.slock)
1958 {
1959 DEFINE_WAIT(wait);
1960
1961 for (;;) {
1962 prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
1963 TASK_UNINTERRUPTIBLE);
1964 spin_unlock_bh(&sk->sk_lock.slock);
1965 schedule();
1966 spin_lock_bh(&sk->sk_lock.slock);
1967 if (!sock_owned_by_user(sk))
1968 break;
1969 }
1970 finish_wait(&sk->sk_lock.wq, &wait);
1971 }
1972
1973 static void __release_sock(struct sock *sk)
1974 __releases(&sk->sk_lock.slock)
1975 __acquires(&sk->sk_lock.slock)
1976 {
1977 struct sk_buff *skb = sk->sk_backlog.head;
1978
1979 do {
1980 sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
1981 bh_unlock_sock(sk);
1982
1983 do {
1984 struct sk_buff *next = skb->next;
1985
1986 prefetch(next);
1987 WARN_ON_ONCE(skb_dst_is_noref(skb));
1988 skb->next = NULL;
1989 sk_backlog_rcv(sk, skb);
1990
1991 /*
1992 * We are in process context here with softirqs
1993 * disabled, use cond_resched_softirq() to preempt.
1994 * This is safe to do because we've taken the backlog
1995 * queue private:
1996 */
1997 cond_resched_softirq();
1998
1999 skb = next;
2000 } while (skb != NULL);
2001
2002 bh_lock_sock(sk);
2003 } while ((skb = sk->sk_backlog.head) != NULL);
2004
2005 /*
2006 * Doing the zeroing here guarantee we can not loop forever
2007 * while a wild producer attempts to flood us.
2008 */
2009 sk->sk_backlog.len = 0;
2010 }
2011
2012 /**
2013 * sk_wait_data - wait for data to arrive at sk_receive_queue
2014 * @sk: sock to wait on
2015 * @timeo: for how long
2016 * @skb: last skb seen on sk_receive_queue
2017 *
2018 * Now socket state including sk->sk_err is changed only under lock,
2019 * hence we may omit checks after joining wait queue.
2020 * We check receive queue before schedule() only as optimization;
2021 * it is very likely that release_sock() added new data.
2022 */
2023 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb)
2024 {
2025 int rc;
2026 DEFINE_WAIT(wait);
2027
2028 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
2029 sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2030 rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb);
2031 sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2032 finish_wait(sk_sleep(sk), &wait);
2033 return rc;
2034 }
2035 EXPORT_SYMBOL(sk_wait_data);
2036
2037 /**
2038 * __sk_mem_schedule - increase sk_forward_alloc and memory_allocated
2039 * @sk: socket
2040 * @size: memory size to allocate
2041 * @kind: allocation type
2042 *
2043 * If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
2044 * rmem allocation. This function assumes that protocols which have
2045 * memory_pressure use sk_wmem_queued as write buffer accounting.
2046 */
2047 int __sk_mem_schedule(struct sock *sk, int size, int kind)
2048 {
2049 struct proto *prot = sk->sk_prot;
2050 int amt = sk_mem_pages(size);
2051 long allocated;
2052
2053 sk->sk_forward_alloc += amt * SK_MEM_QUANTUM;
2054
2055 allocated = sk_memory_allocated_add(sk, amt);
2056
2057 if (mem_cgroup_sockets_enabled && sk->sk_memcg &&
2058 !mem_cgroup_charge_skmem(sk->sk_memcg, amt))
2059 goto suppress_allocation;
2060
2061 /* Under limit. */
2062 if (allocated <= sk_prot_mem_limits(sk, 0)) {
2063 sk_leave_memory_pressure(sk);
2064 return 1;
2065 }
2066
2067 /* Under pressure. */
2068 if (allocated > sk_prot_mem_limits(sk, 1))
2069 sk_enter_memory_pressure(sk);
2070
2071 /* Over hard limit. */
2072 if (allocated > sk_prot_mem_limits(sk, 2))
2073 goto suppress_allocation;
2074
2075 /* guarantee minimum buffer size under pressure */
2076 if (kind == SK_MEM_RECV) {
2077 if (atomic_read(&sk->sk_rmem_alloc) < prot->sysctl_rmem[0])
2078 return 1;
2079
2080 } else { /* SK_MEM_SEND */
2081 if (sk->sk_type == SOCK_STREAM) {
2082 if (sk->sk_wmem_queued < prot->sysctl_wmem[0])
2083 return 1;
2084 } else if (atomic_read(&sk->sk_wmem_alloc) <
2085 prot->sysctl_wmem[0])
2086 return 1;
2087 }
2088
2089 if (sk_has_memory_pressure(sk)) {
2090 int alloc;
2091
2092 if (!sk_under_memory_pressure(sk))
2093 return 1;
2094 alloc = sk_sockets_allocated_read_positive(sk);
2095 if (sk_prot_mem_limits(sk, 2) > alloc *
2096 sk_mem_pages(sk->sk_wmem_queued +
2097 atomic_read(&sk->sk_rmem_alloc) +
2098 sk->sk_forward_alloc))
2099 return 1;
2100 }
2101
2102 suppress_allocation:
2103
2104 if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
2105 sk_stream_moderate_sndbuf(sk);
2106
2107 /* Fail only if socket is _under_ its sndbuf.
2108 * In this case we cannot block, so that we have to fail.
2109 */
2110 if (sk->sk_wmem_queued + size >= sk->sk_sndbuf)
2111 return 1;
2112 }
2113
2114 trace_sock_exceed_buf_limit(sk, prot, allocated);
2115
2116 /* Alas. Undo changes. */
2117 sk->sk_forward_alloc -= amt * SK_MEM_QUANTUM;
2118
2119 sk_memory_allocated_sub(sk, amt);
2120
2121 if (mem_cgroup_sockets_enabled && sk->sk_memcg)
2122 mem_cgroup_uncharge_skmem(sk->sk_memcg, amt);
2123
2124 return 0;
2125 }
2126 EXPORT_SYMBOL(__sk_mem_schedule);
2127
2128 /**
2129 * __sk_mem_reclaim - reclaim memory_allocated
2130 * @sk: socket
2131 * @amount: number of bytes (rounded down to a SK_MEM_QUANTUM multiple)
2132 */
2133 void __sk_mem_reclaim(struct sock *sk, int amount)
2134 {
2135 amount >>= SK_MEM_QUANTUM_SHIFT;
2136 sk_memory_allocated_sub(sk, amount);
2137 sk->sk_forward_alloc -= amount << SK_MEM_QUANTUM_SHIFT;
2138
2139 if (mem_cgroup_sockets_enabled && sk->sk_memcg)
2140 mem_cgroup_uncharge_skmem(sk->sk_memcg, amount);
2141
2142 if (sk_under_memory_pressure(sk) &&
2143 (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
2144 sk_leave_memory_pressure(sk);
2145 }
2146 EXPORT_SYMBOL(__sk_mem_reclaim);
2147
2148
2149 /*
2150 * Set of default routines for initialising struct proto_ops when
2151 * the protocol does not support a particular function. In certain
2152 * cases where it makes no sense for a protocol to have a "do nothing"
2153 * function, some default processing is provided.
2154 */
2155
2156 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
2157 {
2158 return -EOPNOTSUPP;
2159 }
2160 EXPORT_SYMBOL(sock_no_bind);
2161
2162 int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
2163 int len, int flags)
2164 {
2165 return -EOPNOTSUPP;
2166 }
2167 EXPORT_SYMBOL(sock_no_connect);
2168
2169 int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
2170 {
2171 return -EOPNOTSUPP;
2172 }
2173 EXPORT_SYMBOL(sock_no_socketpair);
2174
2175 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags)
2176 {
2177 return -EOPNOTSUPP;
2178 }
2179 EXPORT_SYMBOL(sock_no_accept);
2180
2181 int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
2182 int *len, int peer)
2183 {
2184 return -EOPNOTSUPP;
2185 }
2186 EXPORT_SYMBOL(sock_no_getname);
2187
2188 unsigned int sock_no_poll(struct file *file, struct socket *sock, poll_table *pt)
2189 {
2190 return 0;
2191 }
2192 EXPORT_SYMBOL(sock_no_poll);
2193
2194 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
2195 {
2196 return -EOPNOTSUPP;
2197 }
2198 EXPORT_SYMBOL(sock_no_ioctl);
2199
2200 int sock_no_listen(struct socket *sock, int backlog)
2201 {
2202 return -EOPNOTSUPP;
2203 }
2204 EXPORT_SYMBOL(sock_no_listen);
2205
2206 int sock_no_shutdown(struct socket *sock, int how)
2207 {
2208 return -EOPNOTSUPP;
2209 }
2210 EXPORT_SYMBOL(sock_no_shutdown);
2211
2212 int sock_no_setsockopt(struct socket *sock, int level, int optname,
2213 char __user *optval, unsigned int optlen)
2214 {
2215 return -EOPNOTSUPP;
2216 }
2217 EXPORT_SYMBOL(sock_no_setsockopt);
2218
2219 int sock_no_getsockopt(struct socket *sock, int level, int optname,
2220 char __user *optval, int __user *optlen)
2221 {
2222 return -EOPNOTSUPP;
2223 }
2224 EXPORT_SYMBOL(sock_no_getsockopt);
2225
2226 int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
2227 {
2228 return -EOPNOTSUPP;
2229 }
2230 EXPORT_SYMBOL(sock_no_sendmsg);
2231
2232 int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len,
2233 int flags)
2234 {
2235 return -EOPNOTSUPP;
2236 }
2237 EXPORT_SYMBOL(sock_no_recvmsg);
2238
2239 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
2240 {
2241 /* Mirror missing mmap method error code */
2242 return -ENODEV;
2243 }
2244 EXPORT_SYMBOL(sock_no_mmap);
2245
2246 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
2247 {
2248 ssize_t res;
2249 struct msghdr msg = {.msg_flags = flags};
2250 struct kvec iov;
2251 char *kaddr = kmap(page);
2252 iov.iov_base = kaddr + offset;
2253 iov.iov_len = size;
2254 res = kernel_sendmsg(sock, &msg, &iov, 1, size);
2255 kunmap(page);
2256 return res;
2257 }
2258 EXPORT_SYMBOL(sock_no_sendpage);
2259
2260 /*
2261 * Default Socket Callbacks
2262 */
2263
2264 static void sock_def_wakeup(struct sock *sk)
2265 {
2266 struct socket_wq *wq;
2267
2268 rcu_read_lock();
2269 wq = rcu_dereference(sk->sk_wq);
2270 if (skwq_has_sleeper(wq))
2271 wake_up_interruptible_all(&wq->wait);
2272 rcu_read_unlock();
2273 }
2274
2275 static void sock_def_error_report(struct sock *sk)
2276 {
2277 struct socket_wq *wq;
2278
2279 rcu_read_lock();
2280 wq = rcu_dereference(sk->sk_wq);
2281 if (skwq_has_sleeper(wq))
2282 wake_up_interruptible_poll(&wq->wait, POLLERR);
2283 sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
2284 rcu_read_unlock();
2285 }
2286
2287 static void sock_def_readable(struct sock *sk)
2288 {
2289 struct socket_wq *wq;
2290
2291 rcu_read_lock();
2292 wq = rcu_dereference(sk->sk_wq);
2293 if (skwq_has_sleeper(wq))
2294 wake_up_interruptible_sync_poll(&wq->wait, POLLIN | POLLPRI |
2295 POLLRDNORM | POLLRDBAND);
2296 sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
2297 rcu_read_unlock();
2298 }
2299
2300 static void sock_def_write_space(struct sock *sk)
2301 {
2302 struct socket_wq *wq;
2303
2304 rcu_read_lock();
2305
2306 /* Do not wake up a writer until he can make "significant"
2307 * progress. --DaveM
2308 */
2309 if ((atomic_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) {
2310 wq = rcu_dereference(sk->sk_wq);
2311 if (skwq_has_sleeper(wq))
2312 wake_up_interruptible_sync_poll(&wq->wait, POLLOUT |
2313 POLLWRNORM | POLLWRBAND);
2314
2315 /* Should agree with poll, otherwise some programs break */
2316 if (sock_writeable(sk))
2317 sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
2318 }
2319
2320 rcu_read_unlock();
2321 }
2322
2323 static void sock_def_destruct(struct sock *sk)
2324 {
2325 }
2326
2327 void sk_send_sigurg(struct sock *sk)
2328 {
2329 if (sk->sk_socket && sk->sk_socket->file)
2330 if (send_sigurg(&sk->sk_socket->file->f_owner))
2331 sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
2332 }
2333 EXPORT_SYMBOL(sk_send_sigurg);
2334
2335 void sk_reset_timer(struct sock *sk, struct timer_list* timer,
2336 unsigned long expires)
2337 {
2338 if (!mod_timer(timer, expires))
2339 sock_hold(sk);
2340 }
2341 EXPORT_SYMBOL(sk_reset_timer);
2342
2343 void sk_stop_timer(struct sock *sk, struct timer_list* timer)
2344 {
2345 if (del_timer(timer))
2346 __sock_put(sk);
2347 }
2348 EXPORT_SYMBOL(sk_stop_timer);
2349
2350 void sock_init_data(struct socket *sock, struct sock *sk)
2351 {
2352 skb_queue_head_init(&sk->sk_receive_queue);
2353 skb_queue_head_init(&sk->sk_write_queue);
2354 skb_queue_head_init(&sk->sk_error_queue);
2355
2356 sk->sk_send_head = NULL;
2357
2358 init_timer(&sk->sk_timer);
2359
2360 sk->sk_allocation = GFP_KERNEL;
2361 sk->sk_rcvbuf = sysctl_rmem_default;
2362 sk->sk_sndbuf = sysctl_wmem_default;
2363 sk->sk_state = TCP_CLOSE;
2364 sk_set_socket(sk, sock);
2365
2366 sock_set_flag(sk, SOCK_ZAPPED);
2367
2368 if (sock) {
2369 sk->sk_type = sock->type;
2370 sk->sk_wq = sock->wq;
2371 sock->sk = sk;
2372 } else
2373 sk->sk_wq = NULL;
2374
2375 rwlock_init(&sk->sk_callback_lock);
2376 lockdep_set_class_and_name(&sk->sk_callback_lock,
2377 af_callback_keys + sk->sk_family,
2378 af_family_clock_key_strings[sk->sk_family]);
2379
2380 sk->sk_state_change = sock_def_wakeup;
2381 sk->sk_data_ready = sock_def_readable;
2382 sk->sk_write_space = sock_def_write_space;
2383 sk->sk_error_report = sock_def_error_report;
2384 sk->sk_destruct = sock_def_destruct;
2385
2386 sk->sk_frag.page = NULL;
2387 sk->sk_frag.offset = 0;
2388 sk->sk_peek_off = -1;
2389
2390 sk->sk_peer_pid = NULL;
2391 sk->sk_peer_cred = NULL;
2392 sk->sk_write_pending = 0;
2393 sk->sk_rcvlowat = 1;
2394 sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT;
2395 sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
2396
2397 sk->sk_stamp = ktime_set(-1L, 0);
2398
2399 #ifdef CONFIG_NET_RX_BUSY_POLL
2400 sk->sk_napi_id = 0;
2401 sk->sk_ll_usec = sysctl_net_busy_read;
2402 #endif
2403
2404 sk->sk_max_pacing_rate = ~0U;
2405 sk->sk_pacing_rate = ~0U;
2406 sk->sk_incoming_cpu = -1;
2407 /*
2408 * Before updating sk_refcnt, we must commit prior changes to memory
2409 * (Documentation/RCU/rculist_nulls.txt for details)
2410 */
2411 smp_wmb();
2412 atomic_set(&sk->sk_refcnt, 1);
2413 atomic_set(&sk->sk_drops, 0);
2414 }
2415 EXPORT_SYMBOL(sock_init_data);
2416
2417 void lock_sock_nested(struct sock *sk, int subclass)
2418 {
2419 might_sleep();
2420 spin_lock_bh(&sk->sk_lock.slock);
2421 if (sk->sk_lock.owned)
2422 __lock_sock(sk);
2423 sk->sk_lock.owned = 1;
2424 spin_unlock(&sk->sk_lock.slock);
2425 /*
2426 * The sk_lock has mutex_lock() semantics here:
2427 */
2428 mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
2429 local_bh_enable();
2430 }
2431 EXPORT_SYMBOL(lock_sock_nested);
2432
2433 void release_sock(struct sock *sk)
2434 {
2435 /*
2436 * The sk_lock has mutex_unlock() semantics:
2437 */
2438 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
2439
2440 spin_lock_bh(&sk->sk_lock.slock);
2441 if (sk->sk_backlog.tail)
2442 __release_sock(sk);
2443
2444 /* Warning : release_cb() might need to release sk ownership,
2445 * ie call sock_release_ownership(sk) before us.
2446 */
2447 if (sk->sk_prot->release_cb)
2448 sk->sk_prot->release_cb(sk);
2449
2450 sock_release_ownership(sk);
2451 if (waitqueue_active(&sk->sk_lock.wq))
2452 wake_up(&sk->sk_lock.wq);
2453 spin_unlock_bh(&sk->sk_lock.slock);
2454 }
2455 EXPORT_SYMBOL(release_sock);
2456
2457 /**
2458 * lock_sock_fast - fast version of lock_sock
2459 * @sk: socket
2460 *
2461 * This version should be used for very small section, where process wont block
2462 * return false if fast path is taken
2463 * sk_lock.slock locked, owned = 0, BH disabled
2464 * return true if slow path is taken
2465 * sk_lock.slock unlocked, owned = 1, BH enabled
2466 */
2467 bool lock_sock_fast(struct sock *sk)
2468 {
2469 might_sleep();
2470 spin_lock_bh(&sk->sk_lock.slock);
2471
2472 if (!sk->sk_lock.owned)
2473 /*
2474 * Note : We must disable BH
2475 */
2476 return false;
2477
2478 __lock_sock(sk);
2479 sk->sk_lock.owned = 1;
2480 spin_unlock(&sk->sk_lock.slock);
2481 /*
2482 * The sk_lock has mutex_lock() semantics here:
2483 */
2484 mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
2485 local_bh_enable();
2486 return true;
2487 }
2488 EXPORT_SYMBOL(lock_sock_fast);
2489
2490 int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp)
2491 {
2492 struct timeval tv;
2493 if (!sock_flag(sk, SOCK_TIMESTAMP))
2494 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2495 tv = ktime_to_timeval(sk->sk_stamp);
2496 if (tv.tv_sec == -1)
2497 return -ENOENT;
2498 if (tv.tv_sec == 0) {
2499 sk->sk_stamp = ktime_get_real();
2500 tv = ktime_to_timeval(sk->sk_stamp);
2501 }
2502 return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0;
2503 }
2504 EXPORT_SYMBOL(sock_get_timestamp);
2505
2506 int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp)
2507 {
2508 struct timespec ts;
2509 if (!sock_flag(sk, SOCK_TIMESTAMP))
2510 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2511 ts = ktime_to_timespec(sk->sk_stamp);
2512 if (ts.tv_sec == -1)
2513 return -ENOENT;
2514 if (ts.tv_sec == 0) {
2515 sk->sk_stamp = ktime_get_real();
2516 ts = ktime_to_timespec(sk->sk_stamp);
2517 }
2518 return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0;
2519 }
2520 EXPORT_SYMBOL(sock_get_timestampns);
2521
2522 void sock_enable_timestamp(struct sock *sk, int flag)
2523 {
2524 if (!sock_flag(sk, flag)) {
2525 unsigned long previous_flags = sk->sk_flags;
2526
2527 sock_set_flag(sk, flag);
2528 /*
2529 * we just set one of the two flags which require net
2530 * time stamping, but time stamping might have been on
2531 * already because of the other one
2532 */
2533 if (sock_needs_netstamp(sk) &&
2534 !(previous_flags & SK_FLAGS_TIMESTAMP))
2535 net_enable_timestamp();
2536 }
2537 }
2538
2539 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
2540 int level, int type)
2541 {
2542 struct sock_exterr_skb *serr;
2543 struct sk_buff *skb;
2544 int copied, err;
2545
2546 err = -EAGAIN;
2547 skb = sock_dequeue_err_skb(sk);
2548 if (skb == NULL)
2549 goto out;
2550
2551 copied = skb->len;
2552 if (copied > len) {
2553 msg->msg_flags |= MSG_TRUNC;
2554 copied = len;
2555 }
2556 err = skb_copy_datagram_msg(skb, 0, msg, copied);
2557 if (err)
2558 goto out_free_skb;
2559
2560 sock_recv_timestamp(msg, sk, skb);
2561
2562 serr = SKB_EXT_ERR(skb);
2563 put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee);
2564
2565 msg->msg_flags |= MSG_ERRQUEUE;
2566 err = copied;
2567
2568 out_free_skb:
2569 kfree_skb(skb);
2570 out:
2571 return err;
2572 }
2573 EXPORT_SYMBOL(sock_recv_errqueue);
2574
2575 /*
2576 * Get a socket option on an socket.
2577 *
2578 * FIX: POSIX 1003.1g is very ambiguous here. It states that
2579 * asynchronous errors should be reported by getsockopt. We assume
2580 * this means if you specify SO_ERROR (otherwise whats the point of it).
2581 */
2582 int sock_common_getsockopt(struct socket *sock, int level, int optname,
2583 char __user *optval, int __user *optlen)
2584 {
2585 struct sock *sk = sock->sk;
2586
2587 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2588 }
2589 EXPORT_SYMBOL(sock_common_getsockopt);
2590
2591 #ifdef CONFIG_COMPAT
2592 int compat_sock_common_getsockopt(struct socket *sock, int level, int optname,
2593 char __user *optval, int __user *optlen)
2594 {
2595 struct sock *sk = sock->sk;
2596
2597 if (sk->sk_prot->compat_getsockopt != NULL)
2598 return sk->sk_prot->compat_getsockopt(sk, level, optname,
2599 optval, optlen);
2600 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2601 }
2602 EXPORT_SYMBOL(compat_sock_common_getsockopt);
2603 #endif
2604
2605 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
2606 int flags)
2607 {
2608 struct sock *sk = sock->sk;
2609 int addr_len = 0;
2610 int err;
2611
2612 err = sk->sk_prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT,
2613 flags & ~MSG_DONTWAIT, &addr_len);
2614 if (err >= 0)
2615 msg->msg_namelen = addr_len;
2616 return err;
2617 }
2618 EXPORT_SYMBOL(sock_common_recvmsg);
2619
2620 /*
2621 * Set socket options on an inet socket.
2622 */
2623 int sock_common_setsockopt(struct socket *sock, int level, int optname,
2624 char __user *optval, unsigned int optlen)
2625 {
2626 struct sock *sk = sock->sk;
2627
2628 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2629 }
2630 EXPORT_SYMBOL(sock_common_setsockopt);
2631
2632 #ifdef CONFIG_COMPAT
2633 int compat_sock_common_setsockopt(struct socket *sock, int level, int optname,
2634 char __user *optval, unsigned int optlen)
2635 {
2636 struct sock *sk = sock->sk;
2637
2638 if (sk->sk_prot->compat_setsockopt != NULL)
2639 return sk->sk_prot->compat_setsockopt(sk, level, optname,
2640 optval, optlen);
2641 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2642 }
2643 EXPORT_SYMBOL(compat_sock_common_setsockopt);
2644 #endif
2645
2646 void sk_common_release(struct sock *sk)
2647 {
2648 if (sk->sk_prot->destroy)
2649 sk->sk_prot->destroy(sk);
2650
2651 /*
2652 * Observation: when sock_common_release is called, processes have
2653 * no access to socket. But net still has.
2654 * Step one, detach it from networking:
2655 *
2656 * A. Remove from hash tables.
2657 */
2658
2659 sk->sk_prot->unhash(sk);
2660
2661 /*
2662 * In this point socket cannot receive new packets, but it is possible
2663 * that some packets are in flight because some CPU runs receiver and
2664 * did hash table lookup before we unhashed socket. They will achieve
2665 * receive queue and will be purged by socket destructor.
2666 *
2667 * Also we still have packets pending on receive queue and probably,
2668 * our own packets waiting in device queues. sock_destroy will drain
2669 * receive queue, but transmitted packets will delay socket destruction
2670 * until the last reference will be released.
2671 */
2672
2673 sock_orphan(sk);
2674
2675 xfrm_sk_free_policy(sk);
2676
2677 sk_refcnt_debug_release(sk);
2678
2679 if (sk->sk_frag.page) {
2680 put_page(sk->sk_frag.page);
2681 sk->sk_frag.page = NULL;
2682 }
2683
2684 sock_put(sk);
2685 }
2686 EXPORT_SYMBOL(sk_common_release);
2687
2688 #ifdef CONFIG_PROC_FS
2689 #define PROTO_INUSE_NR 64 /* should be enough for the first time */
2690 struct prot_inuse {
2691 int val[PROTO_INUSE_NR];
2692 };
2693
2694 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
2695
2696 #ifdef CONFIG_NET_NS
2697 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2698 {
2699 __this_cpu_add(net->core.inuse->val[prot->inuse_idx], val);
2700 }
2701 EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2702
2703 int sock_prot_inuse_get(struct net *net, struct proto *prot)
2704 {
2705 int cpu, idx = prot->inuse_idx;
2706 int res = 0;
2707
2708 for_each_possible_cpu(cpu)
2709 res += per_cpu_ptr(net->core.inuse, cpu)->val[idx];
2710
2711 return res >= 0 ? res : 0;
2712 }
2713 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2714
2715 static int __net_init sock_inuse_init_net(struct net *net)
2716 {
2717 net->core.inuse = alloc_percpu(struct prot_inuse);
2718 return net->core.inuse ? 0 : -ENOMEM;
2719 }
2720
2721 static void __net_exit sock_inuse_exit_net(struct net *net)
2722 {
2723 free_percpu(net->core.inuse);
2724 }
2725
2726 static struct pernet_operations net_inuse_ops = {
2727 .init = sock_inuse_init_net,
2728 .exit = sock_inuse_exit_net,
2729 };
2730
2731 static __init int net_inuse_init(void)
2732 {
2733 if (register_pernet_subsys(&net_inuse_ops))
2734 panic("Cannot initialize net inuse counters");
2735
2736 return 0;
2737 }
2738
2739 core_initcall(net_inuse_init);
2740 #else
2741 static DEFINE_PER_CPU(struct prot_inuse, prot_inuse);
2742
2743 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2744 {
2745 __this_cpu_add(prot_inuse.val[prot->inuse_idx], val);
2746 }
2747 EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2748
2749 int sock_prot_inuse_get(struct net *net, struct proto *prot)
2750 {
2751 int cpu, idx = prot->inuse_idx;
2752 int res = 0;
2753
2754 for_each_possible_cpu(cpu)
2755 res += per_cpu(prot_inuse, cpu).val[idx];
2756
2757 return res >= 0 ? res : 0;
2758 }
2759 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2760 #endif
2761
2762 static void assign_proto_idx(struct proto *prot)
2763 {
2764 prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
2765
2766 if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
2767 pr_err("PROTO_INUSE_NR exhausted\n");
2768 return;
2769 }
2770
2771 set_bit(prot->inuse_idx, proto_inuse_idx);
2772 }
2773
2774 static void release_proto_idx(struct proto *prot)
2775 {
2776 if (prot->inuse_idx != PROTO_INUSE_NR - 1)
2777 clear_bit(prot->inuse_idx, proto_inuse_idx);
2778 }
2779 #else
2780 static inline void assign_proto_idx(struct proto *prot)
2781 {
2782 }
2783
2784 static inline void release_proto_idx(struct proto *prot)
2785 {
2786 }
2787 #endif
2788
2789 static void req_prot_cleanup(struct request_sock_ops *rsk_prot)
2790 {
2791 if (!rsk_prot)
2792 return;
2793 kfree(rsk_prot->slab_name);
2794 rsk_prot->slab_name = NULL;
2795 kmem_cache_destroy(rsk_prot->slab);
2796 rsk_prot->slab = NULL;
2797 }
2798
2799 static int req_prot_init(const struct proto *prot)
2800 {
2801 struct request_sock_ops *rsk_prot = prot->rsk_prot;
2802
2803 if (!rsk_prot)
2804 return 0;
2805
2806 rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s",
2807 prot->name);
2808 if (!rsk_prot->slab_name)
2809 return -ENOMEM;
2810
2811 rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name,
2812 rsk_prot->obj_size, 0,
2813 prot->slab_flags, NULL);
2814
2815 if (!rsk_prot->slab) {
2816 pr_crit("%s: Can't create request sock SLAB cache!\n",
2817 prot->name);
2818 return -ENOMEM;
2819 }
2820 return 0;
2821 }
2822
2823 int proto_register(struct proto *prot, int alloc_slab)
2824 {
2825 if (alloc_slab) {
2826 prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0,
2827 SLAB_HWCACHE_ALIGN | prot->slab_flags,
2828 NULL);
2829
2830 if (prot->slab == NULL) {
2831 pr_crit("%s: Can't create sock SLAB cache!\n",
2832 prot->name);
2833 goto out;
2834 }
2835
2836 if (req_prot_init(prot))
2837 goto out_free_request_sock_slab;
2838
2839 if (prot->twsk_prot != NULL) {
2840 prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name);
2841
2842 if (prot->twsk_prot->twsk_slab_name == NULL)
2843 goto out_free_request_sock_slab;
2844
2845 prot->twsk_prot->twsk_slab =
2846 kmem_cache_create(prot->twsk_prot->twsk_slab_name,
2847 prot->twsk_prot->twsk_obj_size,
2848 0,
2849 prot->slab_flags,
2850 NULL);
2851 if (prot->twsk_prot->twsk_slab == NULL)
2852 goto out_free_timewait_sock_slab_name;
2853 }
2854 }
2855
2856 mutex_lock(&proto_list_mutex);
2857 list_add(&prot->node, &proto_list);
2858 assign_proto_idx(prot);
2859 mutex_unlock(&proto_list_mutex);
2860 return 0;
2861
2862 out_free_timewait_sock_slab_name:
2863 kfree(prot->twsk_prot->twsk_slab_name);
2864 out_free_request_sock_slab:
2865 req_prot_cleanup(prot->rsk_prot);
2866
2867 kmem_cache_destroy(prot->slab);
2868 prot->slab = NULL;
2869 out:
2870 return -ENOBUFS;
2871 }
2872 EXPORT_SYMBOL(proto_register);
2873
2874 void proto_unregister(struct proto *prot)
2875 {
2876 mutex_lock(&proto_list_mutex);
2877 release_proto_idx(prot);
2878 list_del(&prot->node);
2879 mutex_unlock(&proto_list_mutex);
2880
2881 kmem_cache_destroy(prot->slab);
2882 prot->slab = NULL;
2883
2884 req_prot_cleanup(prot->rsk_prot);
2885
2886 if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) {
2887 kmem_cache_destroy(prot->twsk_prot->twsk_slab);
2888 kfree(prot->twsk_prot->twsk_slab_name);
2889 prot->twsk_prot->twsk_slab = NULL;
2890 }
2891 }
2892 EXPORT_SYMBOL(proto_unregister);
2893
2894 #ifdef CONFIG_PROC_FS
2895 static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
2896 __acquires(proto_list_mutex)
2897 {
2898 mutex_lock(&proto_list_mutex);
2899 return seq_list_start_head(&proto_list, *pos);
2900 }
2901
2902 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2903 {
2904 return seq_list_next(v, &proto_list, pos);
2905 }
2906
2907 static void proto_seq_stop(struct seq_file *seq, void *v)
2908 __releases(proto_list_mutex)
2909 {
2910 mutex_unlock(&proto_list_mutex);
2911 }
2912
2913 static char proto_method_implemented(const void *method)
2914 {
2915 return method == NULL ? 'n' : 'y';
2916 }
2917 static long sock_prot_memory_allocated(struct proto *proto)
2918 {
2919 return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
2920 }
2921
2922 static char *sock_prot_memory_pressure(struct proto *proto)
2923 {
2924 return proto->memory_pressure != NULL ?
2925 proto_memory_pressure(proto) ? "yes" : "no" : "NI";
2926 }
2927
2928 static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
2929 {
2930
2931 seq_printf(seq, "%-9s %4u %6d %6ld %-3s %6u %-3s %-10s "
2932 "%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
2933 proto->name,
2934 proto->obj_size,
2935 sock_prot_inuse_get(seq_file_net(seq), proto),
2936 sock_prot_memory_allocated(proto),
2937 sock_prot_memory_pressure(proto),
2938 proto->max_header,
2939 proto->slab == NULL ? "no" : "yes",
2940 module_name(proto->owner),
2941 proto_method_implemented(proto->close),
2942 proto_method_implemented(proto->connect),
2943 proto_method_implemented(proto->disconnect),
2944 proto_method_implemented(proto->accept),
2945 proto_method_implemented(proto->ioctl),
2946 proto_method_implemented(proto->init),
2947 proto_method_implemented(proto->destroy),
2948 proto_method_implemented(proto->shutdown),
2949 proto_method_implemented(proto->setsockopt),
2950 proto_method_implemented(proto->getsockopt),
2951 proto_method_implemented(proto->sendmsg),
2952 proto_method_implemented(proto->recvmsg),
2953 proto_method_implemented(proto->sendpage),
2954 proto_method_implemented(proto->bind),
2955 proto_method_implemented(proto->backlog_rcv),
2956 proto_method_implemented(proto->hash),
2957 proto_method_implemented(proto->unhash),
2958 proto_method_implemented(proto->get_port),
2959 proto_method_implemented(proto->enter_memory_pressure));
2960 }
2961
2962 static int proto_seq_show(struct seq_file *seq, void *v)
2963 {
2964 if (v == &proto_list)
2965 seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
2966 "protocol",
2967 "size",
2968 "sockets",
2969 "memory",
2970 "press",
2971 "maxhdr",
2972 "slab",
2973 "module",
2974 "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
2975 else
2976 proto_seq_printf(seq, list_entry(v, struct proto, node));
2977 return 0;
2978 }
2979
2980 static const struct seq_operations proto_seq_ops = {
2981 .start = proto_seq_start,
2982 .next = proto_seq_next,
2983 .stop = proto_seq_stop,
2984 .show = proto_seq_show,
2985 };
2986
2987 static int proto_seq_open(struct inode *inode, struct file *file)
2988 {
2989 return seq_open_net(inode, file, &proto_seq_ops,
2990 sizeof(struct seq_net_private));
2991 }
2992
2993 static const struct file_operations proto_seq_fops = {
2994 .owner = THIS_MODULE,
2995 .open = proto_seq_open,
2996 .read = seq_read,
2997 .llseek = seq_lseek,
2998 .release = seq_release_net,
2999 };
3000
3001 static __net_init int proto_init_net(struct net *net)
3002 {
3003 if (!proc_create("protocols", S_IRUGO, net->proc_net, &proto_seq_fops))
3004 return -ENOMEM;
3005
3006 return 0;
3007 }
3008
3009 static __net_exit void proto_exit_net(struct net *net)
3010 {
3011 remove_proc_entry("protocols", net->proc_net);
3012 }
3013
3014
3015 static __net_initdata struct pernet_operations proto_net_ops = {
3016 .init = proto_init_net,
3017 .exit = proto_exit_net,
3018 };
3019
3020 static int __init proto_init(void)
3021 {
3022 return register_pernet_subsys(&proto_net_ops);
3023 }
3024
3025 subsys_initcall(proto_init);
3026
3027 #endif /* PROC_FS */
Linux kernel - Deliverables
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